Methods for preventing reversion of relaxed keratinous fibers and for relaxing keratinous fibers

ABSTRACT

Methods for preventing reversion of at least one relaxed keratinous fiber and for relaxing at least one keratinous fiber comprising applying compositions comprising at least one sugar chosen from C 3  to C 5  monosaccharides and heating at least one keratinous fiber.

The present invention relates to methods for preventing reversion of atleast one relaxed keratinous fiber and to methods and kits for relaxingat least one keratinous fiber, including human keratinous fibers,comprising at least one sugar chosen from C₃ to C₅ monosaccharides andderivatives thereof.

Hair fiber is a keratinous material which comprises proteins(polypeptides). Many of the polypeptides in hair fibers are bondedtogether or cross-linked with disulfide bonds (—S—S—). A disulfide bondmay be formed from the reaction of two sulfhydryl groups (—SH), one oneach of two cysteine residues, which results in the formation of acystine residue. A cystine residue comprises a cross-link of the formula—CH₂—S—S—CH₂— between 2 polypeptides. While there are other types ofbonds which occur between the polypeptides in hair fibers, such as ionic(salt) bonds, the permanent curling or shape of the hair is essentiallydependent on the disulfide bonds of cystine residues.

In today's market, there is an increasing demand for the hair careproducts referred to as “hair relaxers,” which can relax or straightennaturally curly or kinky hair. Straightening or relaxing the curls ofvery curly hair may increase the manageability and ease of styling ofsuch hair. Hair relaxers may either be applied in a hair salon by aprofessional or in the home by the individual consumer.

Generally, hair relaxing processes are chemical processes which mayalter the aforementioned disulfide bonds between polypeptides in hairfibers and may form lanthionine residues [S[CH₂CH(NH—)(CO—)]₂]. Thus,the term “lanthionizing” is used when one skilled in the art refers tothe relaxing of keratinous fibers. For example, hair fibers may berelaxed or straightened by disrupting the disulfide bonds of the hairfibers with an alkaline or reducing agent. The chemical disruption ofdisulfide bonds with such an agent is generally combined with mechanicalstraightening of the hair, such as combing, and straightening generallyoccurs due to changes in the relative positions of neighboringpolypeptide chains within the hair fiber. This reaction is generallyterminated by rinsing and/or application of a neutralizing composition.

Most frequently, commercial relaxing compositions are in the form ofgels or emulsions that contain varying proportions of strongwater-soluble bases, such as sodium hydroxide (NaOH), or of compositionsthat contain slightly-soluble metal hydroxides, such as calciumhydroxide (Ca(OH)₂), which can be converted in situ to soluble bases,such as guanidine hydroxide. Traditionally, the two main hair relaxersused in the hair care industry for generating hydroxide ions arereferred to as “lye” (lye=sodium hydroxide) relaxers and “no lye”relaxers, such as potassium hydroxide, lithium hydroxide, and calciumhydroxide.

Reducing agents such as compounds comprising at least one thiol groupmay also relax or straighten hair by disrupting disulfide bonds of thehair fibers. More commonly, reducing agents, such as thioglycolates,sulfites, cysteines and their derivatives, are used for texturizingpurposes in hair straightening or relaxing compositions.

The reducing step is generally a reversible reduction reaction ofdisulfide bonds within a keratinous fiber. For example, the reaction ofa thiol-containing reducing agent, RSH, with hair can be represented bythe following reaction scheme, wherein k represents the keratin proteinchain of a keratinous fiber:

k-CH₂—S—S—CH₂-k+RSH≈k-CH₂—S—S—R+k-CH₂—SH  (I)

k-CH₂—S—S—R+RSH≈kCH₂—SH+RS—SR  (II)

Generally, the disulfide product, RS—SR, and any residual reducingagent, RSH, are rinsed from the hair, and then the disulfide bonds arerestored in the neutralizing step. The neutralizing step can berepresented by the following reaction scheme:

With both hydroxide-containing alkaline agents and thiol-containingreducing agent, a high concentration of reducing agent may result inhair damage and a low concentration may result in reversion of the hairto its original curly state. Accordingly, a composition which preventsthe reversion of relaxed hair is desirable.

Sugars and sugar derivatives are one class of the countless number ofcompounds that have been added to hair care compositions. Documenteduses of sugars in hair care compositions include: the use of glucose toimprove the tactile and elastic properties of natural hair (Hollenbergand Mueller, SOFW J. 121(2) (1995)); the use of glucose for hair damageprophylaxis and damaged hair repair (Hollenberg & Matzik, Seifen, Oele,Fette, Wachase 117(1) (1991)); the use of glucose in shampoos(J04266812, assigned to Lion Corp.); the use of trehalose for moistureretention (J06122614, assigned to Shiseido Co. Ltd.); a composition forthe lanthionization of hair comprising a sugar (U.S. Pat. Nos. 5,348,737and 5,641,477, assigned to Avlon Ind. Inc.); the incorporation ofxylobiose into cosmetic compositions to provide enhanced moistureretention and reduce excessive roughness and dryness of the skin andhair (U.S. Pat. No. 5,660,838, assigned to Suntory Ltd.); a compositionfor the regeneration of hair split-ends that contains at least one mono-or di-saccharide (U.S. Pat. No. 4,900,545, assigned to Henkel); haircare compositions to improve hair strength, hold and volume that containC₅ to C₆ carbohydrates such as glucose; the use of fucose in a hairtreatment to prevent split ends (DE29709853, assigned to Goldwell GMBH);and the use of saccharides in a shampoo to improve combing propertiesand control hair damage (J09059134, assigned to Mikuchi Sangyo KK).

In essence, sugars have been applied to hair for many reasons frommoisturizing to enhancing hair growth (J10279439, assigned to KurehaChem. Ind. Co. Ltd.). Clearly, however, not all sugars are the same andnot all sugars impart the same properties when applied to a keratinousfiber.

The inventors have envisaged the application to at least one relaxedkeratinous fiber of at least one composition comprising at least onesugar chosen from C₃ to C₅ monosaccharides and derivatives thereof. Inparticular, the inventors have discovered that methods comprisingapplying these compositions to at least one relaxed keratinous fiber andheating the at least one relaxed keratinous fiber prevent reversion ofthe relaxed hair to a curly or wavy state.

Thus, to achieve at least one of these and other advantages, the presentinvention, in one aspect, provides a method for relaxing keratinousfibers without substantial reversion to the original curly state of thehair using relaxing compositions and compositions comprising at leastone sugar chosen from C₃ to C₅ monosaccharides and derivatives thereof.

Thus, the present invention provides, in one embodiment, a method forpreventing reversion of at least one relaxed keratinous fiber comprising(i) applying to at least one relaxed keratinous fiber a compositioncomprising at least one sugar chosen from C₃ to C₅ monosaccharides andderivatives thereof; and (ii) heating the at least one relaxedkeratinous fiber, wherein the at least one sugar is present in an amounteffective to prevent reversion of the at least one relaxed keratinousfiber, and further wherein the composition is applied prior to or duringheating. In an embodiment, the inventive method further compriseswetting the at least one relaxed keratinous fiber with water prior toapplication of the composition. In an embodiment, the inventive methodfurther comprises rinsing the at least one relaxed keratinous fibersubsequent to heating. In an embodiment, the composition isheat-activated.

The present invention also provides a method for lanthionizingkeratinous fibers to achieve relaxation of at least one keratinous fibercomprising (i) applying at least one relaxing composition to at leastone keratinous fiber for a sufficient period of time to lanthionize saidat least one keratinous fiber; (ii) rinsing the at least one relaxedkeratinous fiber; (iii) applying to the at least one relaxed keratinousfiber a composition comprising at least one sugar chosen from C₃ to C₅monosaccharides and derivatives thereof; and (iv) heating the at leastone relaxed keratinous fiber, wherein the at least one sugar is presentin an amount effective to prevent reversion of the at least one relaxedkeratinous fiber, and further wherein the composition is applied priorto or during heating. In an embodiment, the at least one relaxingcomposition comprises at least one reducing agent chosen from hydroxidecompounds, thiols, sulfites, and derivatives thereof.

Further, the present invention also provides for a multicomponent kitfor lanthionizing keratinous fibers, wherein the kit comprises at leasttwo compartments. A first compartment of the kit contains at least onerelaxing composition and a second compartment contains at least onesugar chosen from C₃ to C₅ monosaccharides and derivatives thereof.

Certain terms used herein are defined below:

As used herein, “at least one” means one or more and thus includesindividual components as well as mixtures/combinations.

“Heating” refers to the use of elevated temperature (i.e., above 45°C.). In one embodiment, “heating refers to the use of temperatures above100° C., such as above 200° C. In one embodiment, the heating in theinventive method may be provided by directly contacting the keratinousfibers with a heat source, e.g., by heat styling of the keratinousfibers. Non-limiting examples of heat styling by direct contact with thekeratinous fibers include flat ironing, and curling methods usingelevated temperatures (such as, for example, curling with a curling ironand/or hot rollers). In another embodiment, the heating in the inventivemethod may be provided by heating the keratinous fibers with a heatsource which may not directly contact the keratinous fibers.Non-limiting examples of heat sources which may not directly contact thekeratinous fibers include blow dryers, hood dryers, heating caps andsteamers.

“Keratinous fibers” as defined herein may be human keratin fibers, andmay be chosen from, for example, hair.

“Lanthionizing,” as used herein, refers to the formation of at least onelanthionine residue, which may accomplish any level of relaxation, forexample, from slight relaxing to straightening.

“Relaxation,” “relaxing,” and “relaxed” as used herein, includes anylevel of relaxing resulting from lanthionization of hair, for example,from slight relaxing to straightening.

A “relaxing composition,” as used herein, refers to compositions, alsocalled “hair relaxers,” which can relax or straighten naturally curly,wavy and/or kinky hair. Relaxing compositions may either be applied in ahair salon by a professional or in the home by the individual consumer.

“Reversion” of at least one relaxed keratinous fiber, as used herein,refers to at least partial return of the at least one relaxed keratinousfiber hair toward the original curly, wavy, and/or kinky state which itwas in prior to relaxation.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention, as claimed. Reference will nowbe made in detail to exemplary embodiments of the present invention.

As described above, sugars have been used in hair care compositions andother treatments for their moisture retaining properties. However, itwas unexpectedly discovered by the present inventors that, in additionto retaining moisture, a certain class of sugars had other propertiesthat made them particularly desirable for use on relaxed keratinousfibers. In particular with respect to hair, compositions comprising atleast one sugar chosen from C₃ to C₅ monosaccharides were found toprevent reversion of relaxed hair. Thus, these compositions may impartto at least one keratinous fiber a higher degree of relaxation or a morepermanent degree or relaxation even after exposure to high humidity,which is known to cause reversion of relaxed hair. This is particularlytrue when the compositions are applied to the hair, and the hair is thenheated.

Thus, the invention provides a method for preventing reversion of atleast one relaxed keratinous fiber comprising (i) applying to at leastone relaxed keratinous fiber a composition comprising at least one sugarchosen from C₃ to C₅ monosaccharides and derivatives thereof; and (ii)heating the at least one relaxed keratinous fiber, wherein the at leastone sugar is present in an amount effective to prevent reversion of theat least one relaxed keratinous fiber, and further wherein thecomposition is applied prior to or during heating. In an embodiment, theinventive method further comprises wetting the at least one keratinousfiber with water prior to application. In an embodiment, the inventivemethod further comprises rinsing the at least one keratinous fibersubsequent to heating. In an embodiment, the composition isheat-activated. The composition may further comprise at least oneadditional sugar.

In an embodiment, the at least one relaxed keratinous fiber is heated at130° C. for 10 seconds. In another embodiment, the at least one relaxedkeratinous fiber is heated at 180° C. for 3 seconds.

The C₃ to C₅ monosaccharides according to the present invention may bechosen from any triose, tetrose and pentose. (Nomenclature: C3-triose,C4-tetrose, C5-pentose). Further, the C₃ to C₅ monosaccharides can bechosen from the D-form, L-form and mixtures of any of the foregoing.Non-limiting examples of C₃ to C₅ monosaccharides include aldopentoses(such as xylose, arabinose, lyxose, and ribose), ketopentoses (such asribulose and xylulose), aldotetroses (such as erythrose and treose),ketotetroses (such as erythrulose), aldotrioses (such as glyceraldehyde)and ketotrioses (such as dihydroxyacetone). The C₃ to C₅ monosaccharidesmay be chosen from C₃ to C₅ monosaccharides comprising aldehyde groups(aldoses), furanoses and other ring structures. The C₃ to C₅monosaccharides may be substituted or unsubstituted.

Derivatives of C₃ to C₅ monosaccharides may be used as the at least onesugar of the present invention. For example, ammonias or primary aminesmay react with the aldehyde or ketone group of a sugar to form an iminederivative (i.e., a compound containing the functional group C═N). Theseimine compounds are sometimes also referred to as Schiff bases. Othernon-limiting examples of derivatives of C₃ to C₅ monosaccharides arehemiacetal derivatives of C₃ to C₅ monosaccharides, hemiketalderivatives of C₃ to C₅ monosaccharides and any oxidized derivatives ofC₃ to C₅ monosaccharides. These derivatives may be formed, for example,from the reaction of the aldehyde or ketone group of a sugar with analcohol. Other exemplary derivatives of C₃ to C₅ monosaccharides mayalso include, but are not limited to, oligosaccharides derived from C₃to C₅ monosaccharides. As previously mentioned, the at least one sugarchosen from C₃ to C₅ monosaccharides may be substituted orunsubstituted. Thus, in one embodiment, the derivatives of C₃ to C₅monosaccharides may be substituted or unsubstituted.

According to the present invention, the at least one sugar is present inthe composition in an amount generally ranging from 0.01% to 10% byweight relative to the total weight of the composition, such as from0.1% to 5% by weight. According to the present invention, an “amounteffective to prevent reversion” of the at least one sugar may bedetermined according to Examples 1-6.

The compositions of the present invention as well as those of theinventive methods may further comprise at least one additional sugarwhich is different from the at least one sugar chosen from C₃ to C₅monosaccharides. The at least one additional sugar may, for example, aidin moisture retention.

The at least one additional sugar may be chosen from any sugar,carbohydrate or carbohydrate moiety. Non-limiting examples of the atleast one additional sugar are monosaccharides, which include, but arenot limited to, three to seven carbon sugars such as pentoses (forexample, ribose, arabinose, xylose, lyxose, ribulose, and xylulose) andhexoses (for example, allose, altrose, glucose, mannose, gulose, idose,galactose, talose, sorbose, psicose, fructose, and tagatose);oligosaccharides such as disaccharides (such as maltose, sucrose,cellobiose, trehalose and lactose); and polysaccharides such as starch,dextrins, cellulose and glycogen. In another embodiment, the at leastone additional sugar is chosen from any aldoses and ketoses. Further,the at least one additional sugar may be substituted or unsubstituted.

According to the present invention, the at least one additional sugar ispresent in the composition in an amount generally ranging from 0.01% to10% by weight relative to the total weight of the composition, such asfrom 0.1% to 5% by weight.

The compositions of the present invention as well as those used in themethods of the present invention may be in the form of a liquid, an oil,a paste, a stick, a dispersion, an emulsion, a lotion, a gel, or acream. These inventive compositions may further comprise at least onesolvent. Non-limiting examples of the at least one solvent include waterand organic solvents. Non-limiting examples of organic solvents includeC₁-C₄ alkanols, such as ethanol and isopropanol; glycerol; glycols andglycol ethers, such as 2-butoxyethanol, propylene glycol, propyleneglycol monomethyl ether, diethylene glycol monoethyl and monomethylether, and aromatic alcohols, such as benzyl alcohol and phenoxyethanol,and mixtures thereof.

Further, these compositions may also comprise at least one suitableadditive chosen from additives commonly used in compositions forkeratinous fibers. Non-limiting examples of the at least one suitableadditive include anionic surfactants, cationic surfactants, nonionicsurfactants, amphoteric surfactants, fragrances, penetrating agents,antioxidants, sequestering agents, opacifying agents, solubilizingagents, emollients, colorants, screening agents (such as sunscreens andUV filters), preserving agents, conditioning agents, proteins, vitamins,silicones, polymers such as thickening polymers, plant oils, mineraloils, synthetic oils and any other additive conventionally used incompositions for the care and/or treatment of keratinous fibers.

The composition comprising the at least one sugar according to thepresent invention generally has a pH ranging from 2 to 10. In anembodiment, the pH of the composition ranges from 3 to 8, such as from 5to 7.

Needless to say, a person skilled in the art will take care to selectthe at least one suitable additive such that the advantageous propertiesof the composition in accordance with the invention are not, or are notsubstantially, adversely affected by the addition(s) envisaged.

The compositions used in the methods and kits of the present inventionmay also be provided as one-part compositions comprising at least onecompound comprising at least one sugar chosen from C₃ to C₅monosaccharides, and, optionally, at least one additional sugar, or inthe form of a multi-component treatment or kit, for example, furthercomprising at least one relaxing composition. The skilled artisan, basedon the stability of the composition and the application envisaged, willbe able to determine how the composition and/or multicomponentcompositions should be stored and mixed. For example, simple sugars suchas C₃ to C₅ monosaccharides are known to be stable at pH levels rangingfrom 4 to 9. In compositions where the pH range is below or above theselevels, e.g., as in a traditional relaxing composition, the sugars wouldbe stored separately and added to the composition only at the time ofapplication.

Thus, the present invention also relates to a kit for relaxing at leastone keratinous fiber comprising at least two compartments, wherein afirst compartment comprises a first composition comprising at least onesugar chosen from C₃ to C₅ monosaccharides and derivatives thereof; anda second composition comprises a second composition comprising at leastone relaxing composition. In one embodiment, at least one compositionfurther comprises at least one additional sugar, different from the atleast one sugar chosen from C₃ to C₅ monosaccharides and derivativesthereof.

As previously discussed, the present invention also provides a methodfor lanthionizing keratinous fibers to achieve relaxation of at leastone keratinous fiber comprising (i) applying at least one relaxingcomposition to at least one keratinous fiber for a sufficient period oftime to lanthionize said at least one keratinous fiber; (ii) rinsing theat least one relaxed keratinous fiber; (iii) applying to the at leastone relaxed keratinous fiber a composition comprising at least one sugarchosen from C₃ to C₅ monosaccharides and derivatives thereof; and (iv)heating the at least one relaxed keratinous fiber, wherein the at leastone sugar is present in an amount effective to prevent reversion of theat least one relaxed keratinous fiber, and further wherein thecomposition is applied prior to or during heating. In an embodiment, theat least one relaxing composition comprises at least one reducing agentchosen from hydroxide compounds, thiols, sulfites, and derivativesthereof. In an embodiment, the at least one reducing agent is present ina concentration ranging from 4% to 20% by weight of the total weight ofsaid at least one relaxing composition. In an embodiment, the at leastone reducing agent is present in a concentration ranging from 7% to 12%by weight of the total weight of said at least one relaxing composition.

Unless otherwise indicated, all numbers expressing quantities ofingredients, reaction conditions, and so forth used in the specificationand claims are to be understood as being modified in all instances bythe term “about.” Accordingly, unless indicated to the contrary, thenumerical parameters set forth in the following specification andattached claims are approximations that may vary depending upon thedesired properties sought to be obtained by the present invention. Atthe very least, and not as an attempt to limit the application of thedoctrine of equivalents to the scope of the claims, each numericalparameter should be construed in light of the number of significantdigits and ordinary rounding approaches.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements. The following examples are intended toillustrate the invention without limiting the scope as a result.

EXAMPLES Example 1 Comparison of the Effect of 5% D-Xylose vs. Water onthe Percent Reversion of Hair Relaxed with 2.5% Sodium Hydroxide

Virgin African-American (kinky) hair was processed and 2.5% sodiumhydroxide for 20 min at room temperature. Next, the sodium hydroxidesolution was washed off, the swatch was profusely rinsed with tepidwater, and the treatment solution was applied for 5 min at roomtemperature. The treatment solutions included: water; 1% D-xylose; and5% D-xylose.

Next, the swatch was briefly rinsed to remove an excess of the treatmentsolution from the hair surface, blow-dried, and heat was applied in theform of five strokes with a flat iron (130° C.). The heat-treated swatchwas rinsed with tepid water, air-dried at 50% RH (25° C.), andmaintained for 24 at 90% RH (25° C.). The percent hair straightening (“%straightening”) was determined as follows:

$\frac{{Length}\mspace{14mu} {of}\mspace{14mu} {the}\mspace{14mu} {curly}\mspace{14mu} {swatch}}{{Total}\mspace{14mu} {length}\mspace{14mu} {of}\mspace{14mu} {the}\mspace{14mu} {swatch}\mspace{14mu} {in}\mspace{14mu} {the}\mspace{14mu} {straight}\mspace{14mu} {configuration}} \times 100(\%)$The percent reversion (“% reversion”)=100%−(% straightening)

TABLE 1 Hair Type % Straightening % Reversion Virgin hair 28.6 — 2.5%NaOH + water 85.7 14.3 2.5% NaOH + 1% D-Xylose 92.8 7.2 2.5% NaOH + 5%D-Xylose 100 0

The data of table 1 show that post-treatment with a D-xylose solutionprevented curl reversion in the relaxed kinky hair.

Example 2 Comparison of the Effect of 5% D-Xylose vs. Water on thePercent Reversion of Hair Relaxed with Various Concentrations of SodiumHydroxide

Virgin African-American (kinky) hair was processed with differentconcentrations of sodium hydroxide for 20 min at room temperature: 1.0%,1.5%, 2.0%, and 2.5% NaOH, respectively. Next, the sodium hydroxidesolution was washed off, the swatch was profusely rinsed with tepidwater, and the treatment solution was applied for 5 min at roomtemperature. The treatment solutions included water and 5% D-xylose.

Next, the swatch was briefly rinsed to remove an excess of the treatmentsolution from the hair surface, blow-dried, and heat was applied in theform of a flat iron for 1 min (130° C.). The heat-treated swatch wasrinsed with tepid water, air-dried at 50% RH (25° C.), and maintainedfor 24 h at 90% RH (25° C.). The percent hair straightening wasdetermined as in Example 1.

Hair Type % Straightening % Reversion Virgin hair 28.6 — 1.0% NaOH +water 42.9 57.1 1.0% NaOH + 5% D-Xylose 57.1 42.9 1.5% NaOH + water 71.428.6 1.5% NaOH + 5% D-Xylose 78.6 21.4 2.0% NaOH + water 80.0 20.0 2.0%NaOH + 5% D-Xylose 100 0 2.5% NaOH + water 100 0 2.5% NaOH + 5% D-Xylose100 0

The data show that post-treatment with a D-xylose solution preventedcurl reversion in the relaxed kinky hair better than post-treatment withwater, even in the case of lower concentrations of sodium hydroxide.

Example 3 Effect of pH of D-Xylose Solutions

Virgin African-American (kinky) hair was processed with 2.0% sodiumhydroxide for 20 min at room. Next, the sodium hydroxide solution waswashed off, the swatch was profusely rinsed with tepid water, and thetreatment solution was applied for 10 min at 45° C. The treatmentsolutions included: buffer solution, pH 2.0; buffer solution, pH 6.0;buffer solution, pH 10.0; 5% D-xylose, pH 2.0; 5% D-xylose, pH 6.5; and5% D-xylose, pH 10. The solutions were buffered using phosphoric acidand sodium hydroxide.

Next, the swatch was briefly rinsed to remove an excess of the treatmentsolution from the hair surface, blow-dried, and heat was applied in theform of a flat iron for 1 min. (130° C.). The heat-treated swatch wasrinsed with tepid water, air-dried at 50% RH (25° C.), and maintainedfor 24 h at 90% RH (25° C.). The percent hair straightening wasdetermined as in Example 1.

Hair Type % Straightening % Reversion Virgin hair 28.6 — 2.0% NaOH +water, pH 2.0 60.0 40.0 2.0% NaOH + 5% D-Xylose, pH 2.0 80.0 20.0 2.0%NaOH + water, pH 6.0 70.0 30.0 2.0% NaOH + 5% D-Xylose, pH 6.5 90.0 10.02.0% NaOH + water, pH 10.0 80.0 20.0 2.0% NaOH + 5% D-Xylose, pH 10.0100 0.00

The data show that post-treatment with a D-Xylose solution preventedreversion of the relaxed hair better than post-treatment with a buffersolution at various pH values.

Example 4 Effect of D-Xylose Concentration on Hair Relaxed with aCommercial Alkali Relaxer

Virgin African-American (kinky) hair was processed with an alkalirelaxer as follows. The commercial cream relaxer was applied to a swatchof hair for 10 min at room temperature. Next, the cream was washed off,the swatch was profusely rinsed with tepid water, and the treatmentsolution was applied for 5 min. The treatment solutions included water;1% D-xylose; 3% D-xylose; and 5% D-xylose.

Next, the swatch was briefly rinsed to remove an excess of the treatmentsolution from the hair surface, blow-dried, and heat was applied in theform of a flat iron for 1 min (175° C.). The heat-treated swatch wasrinsed with tepid water, air-dried at 50% RH (25° C.), and maintainedfor 1 h at 100% RH (25° C.). The percent hair straightening wasdetermined as in Example 1.

Hair Type % Straightening % Reversion Virgin hair 36.4 — Relaxed hair +water 46.2 53.8 Relaxed hair + 1% D-Xylose 69.1 30.9 Relaxed hair + 3%D-Xylose 76.0 24.0 Relaxed hair + 5% D-Xylose 78.0 22.0

The data show that post-treatment with a D-xylose solution preventedreversion of the relaxed hair at various concentrations of D-xylose, ascompared to a post-treatment with water.

Example 5 Effect of D-Xylose Concentration on Hair Relaxed with aCommercial Thioglycolate Relaxer

Virgin African-American (kinky) hair was processed with a commercialthioglycolate cream relaxer as follows. The thioglycolate cream relaxerwas applied to a swatch of kinky hair for 15 min at room temperature(reduced hair). Next, the thioglycolate cream was washed off, the swatchwas profusely rinsed with tepid water, and a hydrogen peroxide cream wasapplied for 5 min. The treatment solutions included: water and 5%D-xylose.

The treatment solutions were applied either between the rinsing of thethioglycolate cream relaxer and the application of the hydrogen peroxidecream, or after the application of the hydrogen peroxide cream,respectively. The treatment solutions was applied for 5 min at roomtemperature. Next, the swatch was briefly rinsed to remove an excess ofthe treatment solution from the hair surface, blow-dried, and heat wasapplied in the form of a flat iron for 30 sec (175° C.). Theheat-treated swatch was rinsed with tepid water, air-dried at 50% RH(25° C.), and maintained for 1 h at 100% RH (25° C.). The percent hairstraightening was determined as in Example 1.

Hair Type % Straightening % Reversion Virgin hair 36.4 — Reduced hair +Hydrogen Peroxide 80.0 20.0 Reduced hair + Hydrogen 86.0 14.0 Peroxide +5% D-Xylose Reduced hair + 5% D-Xylose + 100 0.00 Hydrogen Peroxide

The data show that post-treatment with a D-xylose solution preventedreversion while using a thioglycolate hair relaxer.

1-46. (canceled)
 47. A method for preventing reversion of at least onerelaxed keratinous fiber comprising: applying to at least one relaxedkeratinous fiber a composition comprising at least one sugar chosen fromC₃ to C₅ monosaccharides and derivatives thereof; and heating said atleast one relaxed keratinous fiber, wherein said at least one sugar ispresent in an amount effective to prevent reversion of said at least onerelaxed keratinous fiber, and wherein said composition is applied priorto or during said heating.